The Foreign Office last month rejected Ecuador's request to grant diplomatic status to Assange, which would have given him immunity from arrest.

Julian Assange speaks to the media from the balcony of the Embassy Of Ecuador on May 19, 2017 in London.

Assange, 46, entered the embassy in an apartment in the wealthy district of Knightsbridge to avoid extradition to Sweden to face an allegation of rape, which he denied.

However, the British police could arrest Assange if he leaves the embassy, for breaching his bail conditions when he sought refuge there, Reuters said.

But under British authorities Assange remains in breach of his bail conditions - a separate offence.

His clients has repeatedly pointed out that if he leaves the Embassy where he has been holed up for half a decade he fears being extradited to the U.S. where he could face a severe sentence for leaking hundreds of thousands of secret United States military and diplomatic documents.

But she said she would rule separately on another application from Assange's lawyers asking her to consider whether it would be in the "public interest" to keep the warrant in place.

The judge suggested that Assange could address the British warrant but that he had to first surrender and appear in court. Though that case eventually timed out in May past year, the unwelcome guest has stayed put because he fears being arrested by British police and handed over to the Americans, who want to prosecute him over his WikiLeaks website.

But even if Assange wins, he might decide to remain in the embassy because of fears over a possible secret US indictment against him.

There are no formal charges in against Assange in the USA, though news reports past year suggested the Justice Department was looking into it.

British prosecutors had opposed the removal of the warrant, saying Assange shouldn't be immune from the law simply because he has managed to evade justice for a long time.